This invention relates to a method of joining a tubular member to an arcuate surface, and more particularly to such a method in which a pipe header is joined to a cylindrical transformer tank with the use of a minimum number of fixtures.
In the electrical field, it is often necessary to join a tubular member, such as a pipe header, to an arcuate surface, such as the surface of a cylindrical transformer tank. For such applications, it is desirable to provide a good joint through a method which requires a minimum number of fixtures. Generally, a particular requirement for such a joint is that the pipe header should extend only a prescribed distance into the transformer tank in order to provide adequate electrical clearances.
Although such joints can be provided through well known welding techniques, such techniques exhibit several disadvantages. One such disadvantage is that it is difficult to properly align the flat end surface of the pipe header against the arcuate surface of the cylindrical transformer tank. Generally, proper alignment requires the use of additional fixtures for obtaining the proper alignment and then holding the proper alignment during the joining of the header to the cylindrical transformer tank. One approach has been to provide the arcuate surface of the cylindrical transformer tank with an aperture through which the end portion of the pipe header can be inserted. However, this approach does not allow complete alignment of the pipe header in relation to the transformer tank in that there is no means to maintain the header within the prescribed distance into the tank. The above-mentioned problems are amplified when it is necessary to join a pair of such headers to the cylindrical transformer tank.
Therefore, it is a general object of my invention to provide a method of joining a tubular member to an arcuate surface in which the method requires the minimum use of additional fixtures.
Another object of my invention is to provide such a method for use in joining a pair of spaced pipe headers, which are in fixed relation to each other, to an arcuate surface of a cylindrical transformer tank.